I am working on a project in which I require three separate DC voltages from a single Li-ion battery (cell) of 2600 mAh capacity. I want my Project to be portable, and I only have the single battery to work with. How can I get voltages of 3.3 V, 5 V, and 12 V from my battery?
I measured the battery voltage and it is 4.2V but I understand that the battery voltage will range from about 3V when fully discharged to 4.2V when fully charged, so the power supply needs to accommodate this battery voltage range.
I am using an Arduino Pro Mini 5 V 16 MHz for my project.